Crank handle and method of making the same



May 27, 1924- v H. G. CARLSON CRANK HANDLE AND METHOD OF MAKING THE SAMEOriginal Filed Nov 22.

Patented May 27, 1924.,

FlCE.

HJ'ALMAR G. CARLSON, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO ROCKWOODSPRINKLER COMPANY OF MASSACHUSETTS, OF WORCESTER, MASSACHUSETTS, A

CORPORATION OF MASSACHUSETTS.

CRANK HANDLE AND METHOD OF MAKING THE SAME.

Application filed November 22, 1919, Serial No. 339,991. RenewedNovember 14, 1923.

T all whom it may concern Be it known that I, HJALMAR G. CARLsoN, acitizen of the United States, residing at lVorcester, in the county oflVorcester and State of Massachusetts, have invented a new and usefulCrank Handle and Method of Making the Same, of which the following is aspecification.

This invention relates to a method of making crank handles of sheetmetal and to the crank handleitself, and the principal objects thereofare to provide a method of procedure for making a handle of thatmaterial, the shank of which will be as strong as can be made of solidmaterial, toprovide an improved crank handle or wrench socket of aseamless character in which the socket is integrally connected with oneside of the blank and passes through to the other side to provide astrong construction; to provide such a handle with a shank ofdoublethickness with one surface continuous and seamless; and to providea method of drawing out a part of the blank to produce the wrench end ofthe handle, so that all the parts shall be of one piece and the wrenchsocket will be integral and seamless, thus producing a very strongconstruction; also to provide for concealing all the edges by bringingthem into butt-end relationship to each other or to the other parts ofthe device. Further objects and advantages of the invention will appearhereinafter.

I Reference is to be had to the accompanying drawings, in which Fig. 1is a plan of a flat blank of sheet metal showing the shape in which itis cut out and illustrating the result of the first drawing operation: ai

Fig. 2 is a central longitudinal sectional View of the same; Figs. 3,4,- 5' and 6 are similar sectional views showing the successive resultsof the drawin operations; a i 5 I Fig. is a plan View of the form of theblank shown in Fig. 6;

Fig. 8 is a central longitudinal sectional view showing the result ofthe next two operations Fig. 9 is a plan of the same;

Fig. 10 is an edge view partly in section showing the finished article;and

Fig. 11 is a plan of the same.

To. produce aicrank handle of the form shown in Figs. 1.0 and 11,1 startwith afiat blank cut out to the shape shown in Fig. 1. It isto be notedthat this blank is provided with a. semi-circular end 14 and a smallerend 15 constituting more than asemi-circle to provide a neck at 16.These two ,partsare connected by converging sides 25, shownin the formof straight lines. At the center of the semi-circular end 14 I subjectthe flat blank to a drawing operation ,to provide a cylindricalprojection 17 having a closed-flat end18. i

InFigs. 3, 4t and 5the blank is illustrated in the three stages which itassumes when subjected to three more drawing operations,

form shown in Fig. 5 is not material, that depending upon variouselements as anyone skilled in the art Wlll understand.

The next drawing operation results in the form shown. in Figs. 6 and 7,in which the cylindrical projection 19 is changed to a square socket20,and its size. also somewhat reduced. The outline of the. blank is stillnot changedmaterially, as will appear from comparison of Figures 1 and7.

Inext subject the blank. to a dieing opera tion to cutit .out at thelarge end. only, into a formfor permitting it tobe. fitted into thefinal shape desired, and at th e same time punch out the end of thesocket .20 to get the result shown in Fig. 8., Thewholejof this bottomis punched out. The, changes made in the shape of the flat portion ofthe blank are to provide three substantially rectangular flatprojections 21 centrally spaced ninety degrees from each other andradially located with respect to the center of the square wrench socket20. The three flat projections are connected with each other by shortarcs 22 concentric with the center of the socket 20. The adjacent endsof the two opposite projections '21 are separated from the main body ofthe blank by a pair of notches 23 for permitting of the next opera tion.

This next operation consists in forming the final handle by a series ofbending steps, during which the three projections 21 are doubled over onthe back and. their straight edges brought up against the straight sidesof the socket 20 as shown in Figs. 10 and 11. The walls 24 which arestraight, bounding the notches 23, are also brought up against the innersurface of the socket 20 as the two opposite edges 25 of the blank areturned over into contact with each other throughout the length of thehandle on the underside thereof. This finishes the device around thefour sides of the square socket 20 and leaves that integral, seamlessand extremely strong.

At the other end of the crank a perforation 26 is provided before thebending operation takes place and preferably at the same time that thenotches 23 and projections 21 are formed. Through this is in troducedthe shank end of a handle 27, preferably hollow, although a solid handlecan be introduced if desired. This is upset over the flat surface of thehandle and headed over at 28 to fixit firmly in position.

The bending operation just above de. scribed also involves the bringingtogether of the circular edge 29 up over the headedover portion of thehandle so as to contact with its edge all around and confine it in placeand close all cracks. This adds to the security with which it is held.

I have also shown a bar 30 imbedded in the shank 31. This is not alwaysnecessary but when it is used it is placed in position before thebending operations above described and the edges 25 bent over it tofirmly hold it in position for the purpose of strengthening the handle.

Although I have illustrated and described only a single form of theinvention, I am aware of the fact that modifications can be made thereinby any person skilled in the art without departing from the scope of theinvention as expressed in the claims. Therefore I do not wish to belimited to all the details herein shown and described, or to theparticular number of steps of each kind specified, but what I do claimis:

1. As an article of manufacture, a crank handle consisting of sheetmetal and having a seamless wrench socket, integrally connected with oneside of the shank and passing through the other side.

2. As an article of manufacture, a crank handle comprising a singlepiece of sheet metal having a seamless wrench socket and shank, saidshank being of double thickness, one surface being continuous andseamless and the other surface being formed by bending the edges backagainst the rear surface thereof.

3. As an article of manufacture, a crank handle comprising a shank, asocket formed of a single piece of sheet metal pressed into shape, theshank having its edges bent over on the back into'abutting contact witheach other near the center thereof, and provided with a plurality ofsubstantially quadrangular projections located at right angles to eachother symmetrically surrounding the socket and also bent over on theback into contact with a corresponding number of the sides of saidsocket to help sustain the socket in its normal position.

4. As an article of manufacture, a crank handle consisting of sheetmetal and having a seamless wrench socket, the shank of said handlebeing of double thickness, one surface being continuous and seamless andthe other surface being formed by bending the edges back on the rearsurface thereof until their edges abut against each other throughout thelength of the handle, and also abut against the wrench socket.

5. As an article of manufacture, a sheet metal crank handle having aseamless wrench socket and a shank of double thickness, one thicknessbeing formed by bending the edges back on the rear surface, said socketbeing arranged perpendicular to the flat surface of the shank, and ahandle passing into the end of the shank and engaging the bent overedges of the metal.

6. As an article of manufacture, a sheet metal crank handle having anintegral sheet metal seamless wrench socket square in cross section andperpendicular to one flat surface of the handle, that fiat surface beingseamless and having its edges bent under it and brought into contactwith each other and with the outer surfaces of said socket.

7. As an article of manufacture, a sheet metal crank handle having awrench socket, said handle having a shank of double thick ness, onesurface being continuous and seamless and the other surface being formedby bending the edges back on the rear surface thereof, and a handlehaving its end passing through one wall of the end of the shank, rivetedover on the other side of that wall and engaging the bent over edges ofthe metal.

8. The method of making a sheet metal crank handle which consists incutting out of sheet a flat blank Wider at one end than LIX at the otherand tapering, and providing at the wider end a cup-shaped projectiontherein by a successive series of die-pressing operations to provide anon-circular socket cutting out the end of said socket, cutting aplurality of projections arranged symmetrically around all sides ofsaidsocket but one, bending over the opposite edges of the main portion ofsaid blank until they come into abutting contact on the back, andbending over said projections to bring them into contact on the backwith the surfacesott said socket.

In testimony whereof I have hereunto affixed my signature.

HJALMAR G. CARLSON.

